Drill grinder



July 16, 1940.

F. o. HOAGLAND 2,207,804

DRILL GRINDER Filed Oct. 28, 1938 2 Sheefs-Sheet l IN V EN TOR.

E0. Haag/ana .July 16, 1940. F Q HQAGLAND 2,207,804

DRILL GRINDER Filed Oct. 28, 1938 2 Sheets-Sheet 2 l fyi ,l will' W I n "l nl /6 .Patented July 1s, 1940 ',uiNiTEov STATES PATENT OFFICE DRILL GRINDER Application otober as, 193s, smal No. 237,511A

4 claims. a (o1. 51-219) This invention relates to grinding machines and particularly to a machine lfor grinding the cutting surfaces of a single lip metal cutting deep hole drill.

5 An object of the present invention is Ato provide, a simple and conveniently operated grinding machine enabling a drill of relatively small diameter forl cutting deep holes tol be properly sharpened upon correct oblique angles and with the necessary axial relief.

One feature which enables the above object to be accomplished is that the drill having its cutting surfaces formed or resharpene'd is mounted for rotation about its axis and for simultaneous axial movement toward an abrasive wheel, there being a suitable holder for the drill provided Lwith a cam limiting this axial and rotary movement and there being a suitable support for the drill holder which may be angularly adjusted .o relative to the grinding surface of the abrasive wheel. Another feature of importance is that the axially movable tool holder is supported on a vertically adjusted member and is angularly adg5 instable about two axes at righ-t angles to each other, thus enabling the tool holder to be disposed at any desired oblique angle relative to the abrasive surface.

With the above and other objects in view, the

30 invention may include features of construction and operation set forth in the following speciilcation and illustrated in the accompanying drawings.

In the accompanying drawings annexed hereto 35 and forming a part of this specincation, I have shown the invention embodied in a manually operated drill sharpening machine for deep hole drills of the single lip type, but it will be understood that the invention can be otherwise em- 40 bodied and that the drawings are not to be construed as defining or limiting the scope of the invention, the claims appended to this specification ,being relied upon for that purpose.

In the drawings:

45 Figure l is a complete side elevation of the working parts ofthe drill sharpening machine `disclosed, and claimed in this application.

Fig. 2 is an enlarged view of the axially movable drill holder and a part of the support used 50 in connection with this machine.

Fig. 3 is a front elevation of the machine shown in Fig. 1. Figs. 4 and 5 are respectively an end view and a longitudinal sectional view Of the cam on the drill holder.

Fig. 6 is a sectional view of the supports for mounting the drill being sharpened, and' Fig.A 7 is a perspective view of a. drill showing the surfaces ground by the presentinvention.

In the above mentioned drawings there has 5 been shown but one embodiment of the invention which is now deemed preferable, but itis to be understood that changes and modifications may be made within thegscope of the appended claims 1vgithout departing from the spirit of the inven- 10 Briey and in its preferred aspect, the invention may include the following principal parts: First, a rotatably mounted abrasive wheel, the periphery of which is beveled at oblique angles 15 on opposite sides; second, a vertically adjustable worksupporting arm angularly adjustable substantially in a horizontal plane about an axis at right angles to the axis of rotation of the abrasive wheel; third, a work support on this angularly adjustable arm, the support being angularly adjustable about the axis of the supporting arm; fourth, an axially movable drill holder in the support, the direction of movement being in all adjustments of the support and arm directly 25 toward the abrasive surface of the wheel; and fifth, cam means to axially advance the drill during its rotation and while in engagement with the surfacev of the abrasive wheel.

Referring more in detail to the figures of the drawings, I provide a base or head III in which may be rotatably mounted, preferably upon a horizontal axis, a spindle I I carrying one or more grinding wheels I2 and I3. In the embodiment selected for illustration the spindle II is shown rotated by a directly connected motor Il, there being two similar wheels I2 on one end of the motor shaft and asingle wheel I3 mounted upon the opposite end. The two wheels I2 are or may be entirely similar, two being provided so that one may be vused for roughing and itsl companion wheel may be used for final finishing of any drill sharpening operation. 'Ihe single wheel I3 upon the opposite end of the shaft II is not essential for the sharpening operation but is placed there for general utility and for miscellaneous operations. V

The peripheries of the Itwo adjacent wheels l2 are similarly beveled, these angles being approximately 30 on one side and 45 on the opposite side. 'Ihe longer beveled side at 30 to the axis of the vwheel is used for grinding the oblique front surface of the drill being sharpened and the opposite or shorter beveled surface is used for form- 'is helical so that the proper therewith. A pin I6 extending within the holder I5 enters the hole within the holder for the drill W and engages against the side face of 'the straight ute of the drill and positions the drill in proper rotative relation vto the holder. This holder I5 is slidably mounted within a bracket member or support I1, the position and operations of which will presently be more fully described. On the drill holder I5 is a cam surface I8 preferably forming a portion of the face of a head formed integrally on the work holder. The cam surface I8 engages a pin or other projection I9 outstanding from the forward end of the supporting bracket I1. This cam surface I8 is such that as the drill holder I5 and drill W are rotated they will beadvanced axially in a direction toward and from the surface of one of the abrasive wheels I2. The surface on the cam I8 forward movement drill is provided to form the desired axial relief upon the front cutting surface of the drill. The oblique front face of the drill W is formed by forcing the drill against the beveled periphery of one of the wheels without rotating the drill.

To adjust the' supporting bracket I1 relative to one of the abrasive wheels I2 there is -pro vided a substantially vertical stud mounted in a portion of the head I0 carrying an' arm 2| extending radially therefrom. This arm 2l may be adjusted vertically by means of screw threads formed on the stud 2li and may be also adjusted to any angular position about its vertical axis, the obllquity being indicated by means of graduations 22 provided on the sleeve I9. Means in the form of a collar 23 engaging the threads on the' stud 2li are provided so that the radial arm 2i may be raised or lowered conveniently to any position. A clamping screw within head Il) and engaging the sleeve I9 enables the arm 2l to be clamped in any oblique position.

To mount the bracket I1 upon the radial arm 2l there is provided a member 26 adjustable therealong bymeans of a nut 25 engaging screw threads formed on the arm. By means of the nut 25 and the screw threads therefor the memduring rotation of the ber 24 is adapted tbe held in any adjusted position along the arm 2i. Within this member a spline 26 engages a longitudinal groove in maintaining the member against rotation. Over this member 24 fits the drill supporting bracket I1, there being a worm 21 and worm wheel 28 connection between the member 24 and bracket I1 so that by rotation of the worm 21 through its handle 29 the drill supporting bracket I1 may be angularly adjustable about the horizontal axis of the radial arm 2l.

In operation the drill W is flrst mounted with- 'in its holder I5 with the pin I8 in engagement with the ute of the drill. The arm 2I is then vraised and clamped in proper angular position to engage the front face of the drill W upon one of the beveled sides of one of the wheels I2. The bracket I1 also is angularly adjusted about the axis of arm 2l for this purpose. The end face of the drill will therefore be formed upon an oblique angle corresponding to the oblique adjustment of the arm 2l.i The bracket I1 is then 'within a drill holder I5',

adjusted a arly by the worm 21 and worm wheel 28 to position the drill W against the oppositely beveled side of "a wheel I2. In this position of the bracket I1 the drill W retained within its holder I5 is advanced .against a side of one of the wheels I2 by rotating the holder I5. The cam surface I8 permits the drill during this rotation to form the relieved surface of the drill. This operation takes place with the arm `2I in the samev oblique o r angular axial movement ofadjustment used for the plane oblique end face of the drill.

To restore the surfaces of the wheels I2 a dia- 'mond dressing tool 30 may be mounted in the forward portion of the bracket and passed over the wheel by angularly moving the bracket I1. Preferably one of the wheels I2 may be for rough grinding the drill surfaces and the other wheel adapted to finish grind these surfaces.v Rough grinding of the oblique flat surface of the drill and the axially relieved surface are completed after which the bracket I1 is tilted by rotation of the worm 21 to enable these surfaces to be finish ground on the other wheel.

What I claim is:

1. A drill sharpening machine combination, .a rotatable abrasive wheel having a beveled surface on its periphery, a support adjustable angularly about two axes at right angles to each other, means to adjust said support axially in the directions respectively of said axes,

. ,25 comprising in soL a drill holder rotatably mounted within said support. and a cam on said'holder adapted when rotated with said holder to axially advance said holder in a direction toward the abrasive surface of said wheel.

2. A drill sharpening machine comprising in combination, a rotatable abrasive wheel having y a beveled surface on its.periphery, a support adjustable angularly about two axes at right angles to each other, means to adjust said support axially in the directions respectively of said axes, a drill holder rotatably mounted in said support, means contacting the front cutting surface of a drill to secure said drill therein in predetermined rotative position, and a cam on said holder adapted when rotated with said holder to axially advance said holder andv drill in a direction toward the abrasive surface of said wheel.

3. A drill sharpening machine comprising in combination, a rotatable abrasive wheel, a support adjustable angularly about two axes at right angles to each other,.means to adjust said sup;

port axially in the directions of said axes, a drill holder rotatably mounted within said support, means to retain a drill in predetermined rotative position therein, and a cam on said holder adapted when rotated with's'aid holder to axially advance said holder in a direction toward the abrasive surface of said wheel.

4. A drill sharpening machine comprising in combination, a rotatable abrasive wheel, a support adjustable angularly about two axes at right angles to each other, means to adjust said support axially inthe directions of said axes, a drill holder rotatably mounted in said support, means contacting the front cutting surface ofA a drillto secure said drill therein in predetermined rotative position, and a cam on said holder adapted when rotated with said holder to axially advance said holder and drill'in a direction toward the abrasive surface of said wheel.

FRANK o. HOAGLAND. 

